Chargrilled asparagus and lemon tart – that's the vegetarian menu for a glamorous cast of musicians, actors, writers and artists starting a mass movement today to limit meat eating and combat climate change.

With his daughters, Stella and Mary, Sir Paul McCartney is behind Meat Free Monday, which aims to persuade people to go veggie once a week to reduce greenhouse gas emissions from the world's livestock, among the most serious contributors to global warming.

"We should care about climate change because if we don't, we are going to leave our children and their children in a hell of a mess," Sir Paul told The Independent, which has been given exclusive details of the launch.

The McCartneys have attracted support from across the worlds of showbusiness, science, business and the environment. The singer Chris Martin, Hollywood stars Kevin Spacey and Woody Harrelson, actress Joanna Lumley and Sir Richard Branson are advocating meat-free Mondays.

Support has also come from comedians Ricky Gervais, David Walliams and Matt Lucas, the poet Benjamin Zephaniah and Vogue editor Alexandra Shulman.

Another supporter, Sir David King, the Government's former chief scientist, said: "The carbon and water footprints associated with producing beef are about 20 times larger than maize production. Eating less meat will help the environment."

The UN and Britain are concerned about the environmental impact of livestock, although the Government has shied away from urging people to eat less meat. Vast swathes of the Amazon rainforest are being cut down to make way for cattle ranches and to grow soy for feed. Belching from cows emits vast amounts of methane, which has 21 times the greenhouse effect of carbon dioxide.

According to the UN Food and Agriculture Organisation, meat is responsible for 18 per cent of greenhouse gas emissions, more than transport's 13 per cent. Dr Rajendra Pachauri, the chairman of the UN Intergovernmental Panel on Climate Change, has suggested one vegetarian day a week.

Sir Paul, a life-long vegetarian, said: "Many of us feel helpless in the face of environmental challenges, and it can be hard to know how to sort through the advice about what we can do to make a meaningful contribution to a cleaner, more sustainable, healthier world. Having one designated meat-free day a week is a meaningful change that everyone can make, that goes to the heart of several important political, environmental and ethical issues all at once."

Kelly Osbourne, Laura Bailey, Sharleen Spiteri and Zac Goldsmith, and more than 40 other celebrities will launch the campaign at Inn the Park in St James's Park, central London.

To make vegetarianism a more practical choice, the chefs Oliver Peyton, Giorgio Locatelli, Skye Gyngell and Arthur Potts Dawson are starting meat-free menus beside their usual ones on Mondays. The food writers Nigel Slater and Mark Hix have written recipes for the website, supportmfm.org. Stella McCartney, also a life-long vegetarian, said: "Whether you eat meat or not, you can be part of this decision to limit the meat industry destroying our planet's resources." Her elder sister, Mary, described the change as "an achievable goal."

Sir Paul, who has enlisted the support of George Harrison's widow, Olivia, denied he was using the environment to opportunistically support his vegetarianism. "We didn't start this idea," he said. "It was suggested in a report by the United Nations, who are presumably non-vegetarian. It would be a lot easier to not do this but the link has been established by many scientists and authorities on the subject and it seems wrong to simply ignore it. The issue won't go away."

Carnal knowledge, The meat industry:
*Meat is a "major stressor" on the world's ecosystems, according to a UN report
*Meat makes 1.4 per cent of global GDP but 18 per cent of greenhouse gases
*Forty calories of fossil fuel energy go into producing a calorie of beef, but 2.2 calories for one calorie of plant protein
*Livestock production uses 8 per cent of the world's fresh water
*One billion people are overweight, mostly in the West, where meat consumption is higher. Vegetarians tend to be slimmer
*The World Cancer Research Fund recommends eating 500g red meat a week